From the blog

Claude Opus 4.1 on LiveCodeBench: 62.8% accuracy

Claude Opus 4.1 on LiveCodeBench. Top 10 on LiveCodeBench: 62.8%, rank 8 of 43.

The LayerLens Team covers AI model evaluations, benchmark analysis, and the evolving landscape of AI performance. For the latest independent evaluation data, explore $LayerLens/$.

Summary

Claude Opus 4.1 from Anthropic scored 62.8 on LiveCodeBench, placing it top 10 (rank 8 of 43) on this benchmark. This places the model in the competitive band for LiveCodeBench. Above the cost-effective threshold for most production workloads. Pair with a step-level evaluation harness for agent use cases.

Model details

  • Provider: Anthropic
  • Model key: anthropic/claude-opus-4.1
  • Context length: 200,000 tokens
  • License: Proprietary
  • Open weights: no

Benchmark methodology

Benchmark goal: Evaluate the LLM's ability to understand and generate correct code for programming problems, focusing on logic, syntax, and problem-solving skills.

Scoring metrics:

  • Pass Rate: Percentage of problems for which the LLM generates a correct program that passes all test cases.
  • Execution Time: Time taken by the LLM to generate the code, reflecting efficiency.
  • Code Readability: Qualitative assessment of the generated code based on clarity, structure, and use of meaningful variable names.

Analysis

Key takeaways:

  • Claude Opus demonstrates a capacity for code completion, but performance is bottlenecked by problem-solving ability.
  • The generated code is often syntactically correct, but may have implementation flaws, or is only partially correct.
  • Further improvements are needed in understanding complex mathematical insights.

Failure modes observed

Common failure modes:

  • Incorrect logic in implementation, leading to failing test cases.
  • Inability to handle edge cases, particularly division by zero or incorrect array access.
  • Errors in grouping/categorizing similar elements.

Example: In the Slavic birthday present problem, the model correctly identifies the need to add 1 to the smallest digit but fails to generalize the approach to all possible cases for optimality. Additionally, in the Black and White Cells Problem, the model failed to create a covering with k sized covering cells.

Secondary metrics

  • Readability score: 0.0
  • Toxicity score: 0.000
  • Ethics score: 0.000

Run this evaluation yourself

LayerLens evaluates Claude Opus 4.1 continuously across 11+ benchmarks. To replicate this LiveCodeBench evaluation on your own model, traces, or a different benchmark configuration, open the model in $LayerLens/$.

Source: LayerLens evaluation 690946bd228531518d5fcaf6. Updated 2025-11-04.